Evaluation of body composition is important in countries of different populations and morbidities. One of the groups of morbidity consists of patients with chronic heart failure, where the body fat mass as well as fat-free mass and several other parameters are likely to have an impact on severity and/or outcome of the disease and patient's quality of life. The purpose of the study was to analyze the parameters of body composition in patients with chronic heart failure. Study included 86 patients, fit for the purpose of the study, and 30 practically healthy individuals. Body mass and other measurement data (height, waist circumference, hip circumference and waist-to-hip ratio, anthropometric measurements) were evaluated. Bioelectrical impedance (BIA) was analyzed by BIA 450, BIODYNAMICS (USA) in accordance with standard procedures that are widely accepted. Fat free mass (FFM) was determined by the BIA method. This index was also calculated by prediction equation based on BIA and anthropometric parameters: FFM (kg) = 11.78 + (0.499 x H2/R) + (0.134 x Weight) + (3.449 x gender), where H stands for height in cm, R represents resistance in Ω, Weight is measured in kg and "gender" equals to 0 for females and 1 - for males (3). FFMI equals to the ratio of FFM (kg) to the square of the height; Ratio of FMI - FM (kg) to the square of the height. Study showed that in both patients' and control groups, underweight, as well as overweight individuals are present; also, in both groups, obesity, as BMI category, is most common. Groups (patients vs control) differed in Reactance and FFM (kg) (P<0.009). There was no statistically significant difference between male subgroups of patient and control groups; Valid differences in resistance, lean body mass and fat free mass (kg) were observed between female subgroups. Analysis of body composition characteristics in patients with chronic heart failure revealed that functional classes of heart failure differ in several BIA data, including resistance, Lean body mass (kg) and Fat Free Mass (%).